A check engine light, poor performance and in some cases no start.
The ECM seldom goes bad, it can but it rarely does. A faulty crank sensor could give you those same symptoms. Check all other possibilities before you condem the ECM.
Plug in a code reader. If you get no response, bad ECM or a bad wire/fuse going to or from it. But you may get symptoms of stalling,lack of power,bad fuel milage, and many more things that just don't seem right. But the code scanner will be you best angle of attack.
Bad ECM or ECM relay.
if your ecm is bad, first off the car won't start, your fuel pump won't work, no spark, basically everything shuts down Ok the above can be symptoms of a bad ECM, But that's not the only answer. Your car's Check Engine light will definitely be on. Your car may run like the timing is off, and not get up to speed. Get someone (a mechanic or Auto Zone) to run their code scanner on your car. If it throws out codes that show Ignition Coil A-E failure, CKP and CMP imminent failure, TPS and Pedal Sensor High Circuit, TPS and Pedal Sensor Low Cicuit, MAP and BARO Sensor High and Low. Then you definitely need to get the ECM checked out and replaced. This just happened top a car I worked on and when the ECM was replaced it fixed everything.
Yes
Bad ecm
Number of possibilities.. bad batteries, bad starter, faulty connector the starter, bad ECM, faulty connection to the ECM. Can't narrow it down without knowing more details.
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Bad performance; pingging noise in motor are symptoms of bad gas in a vehicle.
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